策略设计
* 策略模式定义了一系列的算法，并将每一个算法封装起来，而且使他们还可以相互替换。策略模式让算法独立于是用它的客户而独立变化。
/**
* 回家策略接口
* @author dell
*
*/
public interface GoHomeStrategy {
public String goHomeByWhat();
}
package Strategy;
public class AFewPeople implements GoHomeStrategy {
@Override
public String goHomeByWhat() {
return "乘飞机回家！！！";
}
}
package Strategy;
public class MiddleFewPeople implements GoHomeStrategy {
@Override
public String goHomeByWhat() {
return "乘火车回家！！！";
}
}
package Strategy;
public class MorePeople implements GoHomeStrategy {
@Override
public String goHomeByWhat() {
return "乘汽车回家！！！";
}
}
package Strategy;
public class PeopleGoHome {
private GoHomeStrategy strategy;
public PeopleGoHome(GoHomeStrategy strategy) {
super();
this.strategy = strategy;
};
public String getGoHomeStrategy(){
return strategy.goHomeByWhat();
}
}
package Strategy;
/**
* 策略模式定义了一系列的算法，并将每一个算法封装起来，而且使他们还可以相互替换。策略模式让算法独立于是用它的客户而独立变化。
* @author dell
*
*/
public class ClientTest {
public static void main(String[] args) {
GoHomeStrategy s1 = new MorePeople();// 封装起来的算法，完全独立于客户端
PeopleGoHome pg = new PeopleGoHome(s1);// 调用算法策略
System.out.println(pg.getGoHomeStrategy());
GoHomeStrategy s2 = new MiddleFewPeople();
PeopleGoHome pg2 = new PeopleGoHome(s2);
System.out.println(pg2.getGoHomeStrategy());
GoHomeStrategy s3 = new AFewPeople();
PeopleGoHome pg3 = new PeopleGoHome(s3);
System.out.println(pg3.getGoHomeStrategy());
}
}